High-speed divide-by-4/5 prescalers with merged and gates using gainp/gaas hbt and sige hbt technolmes

Abstract

This paper demonstrates the divide-by-4/5 prescalers with merged AND gates in 2-mu m GaInP/GaAs heterojunction bipolar transistor (HBT) and 0.35-mu m SiGe HBT technologies. By biasing the HBT near the peak transit-time frequency (f(T)), the maxinnun operating frequency of a D-type flip-flop can be promoted. At the supply, voltage of 5 the GaInP/GaAs prescaler operates from 30 MHz to 5.2 GHz, and the SiGe prescaler has the higher-speed performance of 1-8 GHz at the cost of power consumption. (c) 2008 Wiley Periodicals, Inc.